Ram Memory 8GB kit (2 x 4GB) DDR3 PC3-12800,1600MHz, 204 PIN SODIMM for laptops at Amazon.com
OWC 8GB PC3-12800 DDR3L 1600MHz SO-DIMM 204 Pin CL11 Memory Module Upgrade Compatible with iMac, Mac Mini, and MacBook Pro (OWC1600DDR3S8GB) at Amazon.com
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Silicon Power Hynix IC Compatible for Apple DDR3 DDR3L 16GB (2 x 8GB) RAM 1600MHz (PC3 12800) 204 pin CL11 1.35V Non ECC Unbuffered SODIMM Laptop Notebook Memory RAM Module Upgrade at Amazon.com
OWC 32GB (2x16GB) PC3-12800 DDR3 1600MHz SO-DIMM 204 Pin CL11 Memory Upgrade Kit Compatible with 2015 iMac (OWC1600DDR3S32P) at Amazon.com
Top Tier PC3-12800 SO-DIMM - 4GB DDR3 1600MHz | Sweetwater